Heat the oil in a medium skillet over moderate heat. Add the onion and cook until soft and beginning to brown, 6 to 7 minutes. Add garlic, chili powder, and coriander and stir. Cook together for 1 minute.

Add this mixture, along with all the remaining ingredients, to the crock pot. Stir and cook on low for 7 to 8 hours. You may need to add more water at the end, though thanks to pre-soaking the beans, I have found it not to be necessary.